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Hard case cars are those sport compacts that fall through the cracks in the industry and consequently get zero love in the aftermarket. Nary a bolt-on to be had, these cars rely on the "universal" parts to conjure higher-flowing exhaust systems or intakes. Heck, most owners are lucky to find a good set of tuner wheels.

A lot of these lost souls are out there and for those unfortunates who lust for boost, there's light at the end of the tunnel--the Thomas Knight Turbo electric supercharger. Designed as a universal supercharger, there are no ungodly pulley configurations or whacked-out axle drives to deal with. In fact, Thomas Knight Turbo (TKT) likens the installation to that of a high-flow intake. TKT says that for most FWD cars, relocating the battery to the trunk and swapping out the air filter opens up enough room to install the unit.

The ESC-400 is the result of 26 years of effort. "I built my first ESC in 1978 while working at Turbo Tech, an FAA and industrial turbo repair station," says TKT's Geoff Knight. "A T11 turbo from a wrecked aircraft was being inspected to see if it caused the engine to fail and it was fine. The FAA never allows parts from any crashed plane to see air time again, so this perfect turbo was deemed un-air-worthy." So he bought it for $25--the core value.

In the early '80s, Knight raced electric RC boats. He installed an Astro-Flight 25 plane motor in a 26-inch SK-daddle boat and ran 27 mph on 26 1.2V NiCads. He decided to try for the record--29 mph average for two laps. More batteries didn't help. Two motors and shafts added 3 mph, so he ran 30 mph with that setup. "I then tried three motors, and even four but nothing went faster. I was frustrated!" he remembers.

Knight then raced 11-foot Hydros for a while and met one of the unlimited drivers at a race. He'd done something similar with model gas boats, so the subject moved to why Knight couldn't go faster. "Simple," he replied, "hydrodynamic drag--too much surface area from too many blades." So Knight eliminated all shafts except one, and ran three motors side-by-side with nylon gears connecting them. That made 35 mph on the first try. By then, the top guys were at 40 mph, so he gave up. Too little, too late. But this lesson eventually led to the production ESC.

Through the years, Knight built about 200 different ESC prototypes, but he never had enough electrical power.

In 1996 Knight looked into a 90-hp DC motor, but it was bigger than a car engine and weighed 1000 pounds. He decided to lower the engine size to a reasonable amount. Even a 2.0-liter engine making 15 psi at 8000 rpm required a 30-hp DC motor. Knight looked into smaller motors, which were still too big and heavy.

"In 1998," says Knight, "I remembered the model boat multiple motors, and realized I may have a solution. Two or more motors; three or four. Why not?" So he applied for patents and researched motors. The 4kw brushless model plane motors were $1,000 each, and each supercharger unit cost $4,500 to make. He made one with three model motors drawing 3,500 watts each at 60 volts. This one used a centrifugal supercharger with gears, then belts, etc. Gears were parasitic, and belts were destroyed in a short time.

Frustration set in again, and Knight built one with some 3kw starter motors. These field winding motors had a ton of torque, but grew hot quickly. After rewinding the starters to different levels, he reached 10,000 rpm and 5.0KW per motor. But the belts and other problems made these centrifugal units work only for someone who wouldn't object to replacing bearings and belts all the time.

Knight was desperate. He'd just replaced 12 belts in a few days on the ESC and wasn't happy. He had a twin-rotor M62 at the shop with a bad nose drive, so he removed the bad nose drive from the Eaton and machined an adaptor to bolt it up. He was sure it would be a poor performer, but went ahead and bolted it into the car.

"It was awesome!" Knight says. "Instant boost, with much faster response than the centrifugal design. Boost was higher at first with the curve going down on a linear path."

Now Knight has patents pending on six different designs, and international patents as well. Two years of constant use on the Avenger test mule has proven the Eaton/electric to be indestructible. The Eaton lasts 158K as a belt-driven supercharger. As an ESC they should last 4 million miles. The electric motors have a 1000-hour life expectancy; at 400 seconds per day that's 24 years.